Nodes are essentially hierarchical entities. So we created an entity to link nodes between them no matter where/what
they are. Tags are meant as tag nodes, we couldn’t be more explicit. But if you didn’t understand here is a schema:

You can see that tags can gather heterogenous nodes coming from different types (pages and projects).
Tags can be used to display a category-navigation on your theme or to simply tidy your backoffice node database.

Did you notice that Tags are related to Nodes entities, not NodesSources? We thought that it would be
easier to manage that way not to forget to tag a specific node translation.
It means that you won’t be able to differenciate tag two NodesSources, if you absolutely need to, we encourage you to create two different nodes.

You will notice that tags work the same way as nodes do. By default, tags names can’t contain special characters in order to be used in URLs.
So we created TagTranslation entities which stand for Tag’s sources:

In that way you will be able to translate your tags for each available languages.